1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_TTY_DRIVER_H
3 #define _LINUX_TTY_DRIVER_H
4
5 #include <linux/export.h>
6 #include <linux/fs.h>
7 #include <linux/kref.h>
8 #include <linux/list.h>
9 #include <linux/cdev.h>
10 #include <linux/uaccess.h>
11 #include <linux/termios.h>
12 #include <linux/seq_file.h>
13
14 struct tty_struct;
15 struct tty_driver;
16 struct serial_icounter_struct;
17 struct serial_struct;
18
19 /**
20 * struct tty_operations -- interface between driver and tty
21 *
22 * @lookup: ``struct tty_struct *()(struct tty_driver *self, struct file *,
23 * int idx)``
24 *
25 * Return the tty device corresponding to @idx, %NULL if there is not
26 * one currently in use and an %ERR_PTR value on error. Called under
27 * %tty_mutex (for now!)
28 *
29 * Optional method. Default behaviour is to use the @self->ttys array.
30 *
31 * @install: ``int ()(struct tty_driver *self, struct tty_struct *tty)``
32 *
33 * Install a new @tty into the @self's internal tables. Used in
34 * conjunction with @lookup and @remove methods.
35 *
36 * Optional method. Default behaviour is to use the @self->ttys array.
37 *
38 * @remove: ``void ()(struct tty_driver *self, struct tty_struct *tty)``
39 *
40 * Remove a closed @tty from the @self's internal tables. Used in
41 * conjunction with @lookup and @remove methods.
42 *
43 * Optional method. Default behaviour is to use the @self->ttys array.
44 *
45 * @open: ``int ()(struct tty_struct *tty, struct file *)``
46 *
47 * This routine is called when a particular @tty device is opened. This
48 * routine is mandatory; if this routine is not filled in, the attempted
49 * open will fail with %ENODEV.
50 *
51 * Required method. Called with tty lock held. May sleep.
52 *
53 * @close: ``void ()(struct tty_struct *tty, struct file *)``
54 *
55 * This routine is called when a particular @tty device is closed. At the
56 * point of return from this call the driver must make no further ldisc
57 * calls of any kind.
58 *
59 * Remark: called even if the corresponding @open() failed.
60 *
61 * Required method. Called with tty lock held. May sleep.
62 *
63 * @shutdown: ``void ()(struct tty_struct *tty)``
64 *
65 * This routine is called under the tty lock when a particular @tty device
66 * is closed for the last time. It executes before the @tty resources
67 * are freed so may execute while another function holds a @tty kref.
68 *
69 * @cleanup: ``void ()(struct tty_struct *tty)``
70 *
71 * This routine is called asynchronously when a particular @tty device
72 * is closed for the last time freeing up the resources. This is
73 * actually the second part of shutdown for routines that might sleep.
74 *
75 * @write: ``ssize_t ()(struct tty_struct *tty, const unsigned char *buf,
76 * size_t count)``
77 *
78 * This routine is called by the kernel to write a series (@count) of
79 * characters (@buf) to the @tty device. The characters may come from
80 * user space or kernel space. This routine will return the
81 * number of characters actually accepted for writing.
82 *
83 * May occur in parallel in special cases. Because this includes panic
84 * paths drivers generally shouldn't try and do clever locking here.
85 *
86 * Optional: Required for writable devices. May not sleep.
87 *
88 * @put_char: ``int ()(struct tty_struct *tty, unsigned char ch)``
89 *
90 * This routine is called by the kernel to write a single character @ch to
91 * the @tty device. If the kernel uses this routine, it must call the
92 * @flush_chars() routine (if defined) when it is done stuffing characters
93 * into the driver. If there is no room in the queue, the character is
94 * ignored.
95 *
96 * Optional: Kernel will use the @write method if not provided. Do not
97 * call this function directly, call tty_put_char().
98 *
99 * @flush_chars: ``void ()(struct tty_struct *tty)``
100 *
101 * This routine is called by the kernel after it has written a
102 * series of characters to the tty device using @put_char().
103 *
104 * Optional. Do not call this function directly, call
105 * tty_driver_flush_chars().
106 *
107 * @write_room: ``unsigned int ()(struct tty_struct *tty)``
108 *
109 * This routine returns the numbers of characters the @tty driver
110 * will accept for queuing to be written. This number is subject
111 * to change as output buffers get emptied, or if the output flow
112 * control is acted.
113 *
114 * The ldisc is responsible for being intelligent about multi-threading of
115 * write_room/write calls
116 *
117 * Required if @write method is provided else not needed. Do not call this
118 * function directly, call tty_write_room()
119 *
120 * @chars_in_buffer: ``unsigned int ()(struct tty_struct *tty)``
121 *
122 * This routine returns the number of characters in the device private
123 * output queue. Used in tty_wait_until_sent() and for poll()
124 * implementation.
125 *
126 * Optional: if not provided, it is assumed there is no queue on the
127 * device. Do not call this function directly, call tty_chars_in_buffer().
128 *
129 * @ioctl: ``int ()(struct tty_struct *tty, unsigned int cmd,
130 * unsigned long arg)``
131 *
132 * This routine allows the @tty driver to implement device-specific
133 * ioctls. If the ioctl number passed in @cmd is not recognized by the
134 * driver, it should return %ENOIOCTLCMD.
135 *
136 * Optional.
137 *
138 * @compat_ioctl: ``long ()(struct tty_struct *tty, unsigned int cmd,
139 * unsigned long arg)``
140 *
141 * Implement ioctl processing for 32 bit process on 64 bit system.
142 *
143 * Optional.
144 *
145 * @set_termios: ``void ()(struct tty_struct *tty, const struct ktermios *old)``
146 *
147 * This routine allows the @tty driver to be notified when device's
148 * termios settings have changed. New settings are in @tty->termios.
149 * Previous settings are passed in the @old argument.
150 *
151 * The API is defined such that the driver should return the actual modes
152 * selected. This means that the driver is responsible for modifying any
153 * bits in @tty->termios it cannot fulfill to indicate the actual modes
154 * being used.
155 *
156 * Optional. Called under the @tty->termios_rwsem. May sleep.
157 *
158 * @ldisc_ok: ``int ()(struct tty_struct *tty, int ldisc)``
159 *
160 * This routine allows the @tty driver to decide if it can deal
161 * with a particular @ldisc.
162 *
163 * Optional. Called under the @tty->ldisc_sem and @tty->termios_rwsem.
164 *
165 * @set_ldisc: ``void ()(struct tty_struct *tty)``
166 *
167 * This routine allows the @tty driver to be notified when the device's
168 * line discipline is being changed. At the point this is done the
169 * discipline is not yet usable.
170 *
171 * Optional. Called under the @tty->ldisc_sem and @tty->termios_rwsem.
172 *
173 * @throttle: ``void ()(struct tty_struct *tty)``
174 *
175 * This routine notifies the @tty driver that input buffers for the line
176 * discipline are close to full, and it should somehow signal that no more
177 * characters should be sent to the @tty.
178 *
179 * Serialization including with @unthrottle() is the job of the ldisc
180 * layer.
181 *
182 * Optional: Always invoke via tty_throttle_safe(). Called under the
183 * @tty->termios_rwsem.
184 *
185 * @unthrottle: ``void ()(struct tty_struct *tty)``
186 *
187 * This routine notifies the @tty driver that it should signal that
188 * characters can now be sent to the @tty without fear of overrunning the
189 * input buffers of the line disciplines.
190 *
191 * Optional. Always invoke via tty_unthrottle(). Called under the
192 * @tty->termios_rwsem.
193 *
194 * @stop: ``void ()(struct tty_struct *tty)``
195 *
196 * This routine notifies the @tty driver that it should stop outputting
197 * characters to the tty device.
198 *
199 * Called with @tty->flow.lock held. Serialized with @start() method.
200 *
201 * Optional. Always invoke via stop_tty().
202 *
203 * @start: ``void ()(struct tty_struct *tty)``
204 *
205 * This routine notifies the @tty driver that it resumed sending
206 * characters to the @tty device.
207 *
208 * Called with @tty->flow.lock held. Serialized with stop() method.
209 *
210 * Optional. Always invoke via start_tty().
211 *
212 * @hangup: ``void ()(struct tty_struct *tty)``
213 *
214 * This routine notifies the @tty driver that it should hang up the @tty
215 * device.
216 *
217 * Optional. Called with tty lock held.
218 *
219 * @break_ctl: ``int ()(struct tty_struct *tty, int state)``
220 *
221 * This optional routine requests the @tty driver to turn on or off BREAK
222 * status on the RS-232 port. If @state is -1, then the BREAK status
223 * should be turned on; if @state is 0, then BREAK should be turned off.
224 *
225 * If this routine is implemented, the high-level tty driver will handle
226 * the following ioctls: %TCSBRK, %TCSBRKP, %TIOCSBRK, %TIOCCBRK.
227 *
228 * If the driver sets %TTY_DRIVER_HARDWARE_BREAK in tty_alloc_driver(),
229 * then the interface will also be called with actual times and the
230 * hardware is expected to do the delay work itself. 0 and -1 are still
231 * used for on/off.
232 *
233 * Optional: Required for %TCSBRK/%BRKP/etc. handling. May sleep.
234 *
235 * @flush_buffer: ``void ()(struct tty_struct *tty)``
236 *
237 * This routine discards device private output buffer. Invoked on close,
238 * hangup, to implement %TCOFLUSH ioctl and similar.
239 *
240 * Optional: if not provided, it is assumed there is no queue on the
241 * device. Do not call this function directly, call
242 * tty_driver_flush_buffer().
243 *
244 * @wait_until_sent: ``void ()(struct tty_struct *tty, int timeout)``
245 *
246 * This routine waits until the device has written out all of the
247 * characters in its transmitter FIFO. Or until @timeout (in jiffies) is
248 * reached.
249 *
250 * Optional: If not provided, the device is assumed to have no FIFO.
251 * Usually correct to invoke via tty_wait_until_sent(). May sleep.
252 *
253 * @send_xchar: ``void ()(struct tty_struct *tty, char ch)``
254 *
255 * This routine is used to send a high-priority XON/XOFF character (@ch)
256 * to the @tty device.
257 *
258 * Optional: If not provided, then the @write method is called under
259 * the @tty->atomic_write_lock to keep it serialized with the ldisc.
260 *
261 * @tiocmget: ``int ()(struct tty_struct *tty)``
262 *
263 * This routine is used to obtain the modem status bits from the @tty
264 * driver.
265 *
266 * Optional: If not provided, then %ENOTTY is returned from the %TIOCMGET
267 * ioctl. Do not call this function directly, call tty_tiocmget().
268 *
269 * @tiocmset: ``int ()(struct tty_struct *tty,
270 * unsigned int set, unsigned int clear)``
271 *
272 * This routine is used to set the modem status bits to the @tty driver.
273 * First, @clear bits should be cleared, then @set bits set.
274 *
275 * Optional: If not provided, then %ENOTTY is returned from the %TIOCMSET
276 * ioctl. Do not call this function directly, call tty_tiocmset().
277 *
278 * @resize: ``int ()(struct tty_struct *tty, struct winsize *ws)``
279 *
280 * Called when a termios request is issued which changes the requested
281 * terminal geometry to @ws.
282 *
283 * Optional: the default action is to update the termios structure
284 * without error. This is usually the correct behaviour. Drivers should
285 * not force errors here if they are not resizable objects (e.g. a serial
286 * line). See tty_do_resize() if you need to wrap the standard method
287 * in your own logic -- the usual case.
288 *
289 * @get_icount: ``int ()(struct tty_struct *tty,
290 * struct serial_icounter *icount)``
291 *
292 * Called when the @tty device receives a %TIOCGICOUNT ioctl. Passed a
293 * kernel structure @icount to complete.
294 *
295 * Optional: called only if provided, otherwise %ENOTTY will be returned.
296 *
297 * @get_serial: ``int ()(struct tty_struct *tty, struct serial_struct *p)``
298 *
299 * Called when the @tty device receives a %TIOCGSERIAL ioctl. Passed a
300 * kernel structure @p (&struct serial_struct) to complete.
301 *
302 * Optional: called only if provided, otherwise %ENOTTY will be returned.
303 * Do not call this function directly, call tty_tiocgserial().
304 *
305 * @set_serial: ``int ()(struct tty_struct *tty, struct serial_struct *p)``
306 *
307 * Called when the @tty device receives a %TIOCSSERIAL ioctl. Passed a
308 * kernel structure @p (&struct serial_struct) to set the values from.
309 *
310 * Optional: called only if provided, otherwise %ENOTTY will be returned.
311 * Do not call this function directly, call tty_tiocsserial().
312 *
313 * @show_fdinfo: ``void ()(struct tty_struct *tty, struct seq_file *m)``
314 *
315 * Called when the @tty device file descriptor receives a fdinfo request
316 * from VFS (to show in /proc/<pid>/fdinfo/). @m should be filled with
317 * information.
318 *
319 * Optional: called only if provided, otherwise nothing is written to @m.
320 * Do not call this function directly, call tty_show_fdinfo().
321 *
322 * @poll_init: ``int ()(struct tty_driver *driver, int line, char *options)``
323 *
324 * kgdboc support (Documentation/dev-tools/kgdb.rst). This routine is
325 * called to initialize the HW for later use by calling @poll_get_char or
326 * @poll_put_char.
327 *
328 * Optional: called only if provided, otherwise skipped as a non-polling
329 * driver.
330 *
331 * @poll_get_char: ``int ()(struct tty_driver *driver, int line)``
332 *
333 * kgdboc support (see @poll_init). @driver should read a character from a
334 * tty identified by @line and return it.
335 *
336 * Optional: called only if @poll_init provided.
337 *
338 * @poll_put_char: ``void ()(struct tty_driver *driver, int line, char ch)``
339 *
340 * kgdboc support (see @poll_init). @driver should write character @ch to
341 * a tty identified by @line.
342 *
343 * Optional: called only if @poll_init provided.
344 *
345 * @proc_show: ``int ()(struct seq_file *m, void *driver)``
346 *
347 * Driver @driver (cast to &struct tty_driver) can show additional info in
348 * /proc/tty/driver/<driver_name>. It is enough to fill in the information
349 * into @m.
350 *
351 * Optional: called only if provided, otherwise no /proc entry created.
352 *
353 * This structure defines the interface between the low-level tty driver and
354 * the tty routines. These routines can be defined. Unless noted otherwise,
355 * they are optional, and can be filled in with a %NULL pointer.
356 */
357 struct tty_operations {
358 struct tty_struct * (*lookup)(struct tty_driver *driver,
359 struct file *filp, int idx);
360 int (*install)(struct tty_driver *driver, struct tty_struct *tty);
361 void (*remove)(struct tty_driver *driver, struct tty_struct *tty);
362 int (*open)(struct tty_struct * tty, struct file * filp);
363 void (*close)(struct tty_struct * tty, struct file * filp);
364 void (*shutdown)(struct tty_struct *tty);
365 void (*cleanup)(struct tty_struct *tty);
366 ssize_t (*write)(struct tty_struct *tty, const u8 *buf, size_t count);
367 int (*put_char)(struct tty_struct *tty, u8 ch);
368 void (*flush_chars)(struct tty_struct *tty);
369 unsigned int (*write_room)(struct tty_struct *tty);
370 unsigned int (*chars_in_buffer)(struct tty_struct *tty);
371 int (*ioctl)(struct tty_struct *tty,
372 unsigned int cmd, unsigned long arg);
373 long (*compat_ioctl)(struct tty_struct *tty,
374 unsigned int cmd, unsigned long arg);
375 void (*set_termios)(struct tty_struct *tty, const struct ktermios *old);
376 void (*throttle)(struct tty_struct * tty);
377 void (*unthrottle)(struct tty_struct * tty);
378 void (*stop)(struct tty_struct *tty);
379 void (*start)(struct tty_struct *tty);
380 void (*hangup)(struct tty_struct *tty);
381 int (*break_ctl)(struct tty_struct *tty, int state);
382 void (*flush_buffer)(struct tty_struct *tty);
383 int (*ldisc_ok)(struct tty_struct *tty, int ldisc);
384 void (*set_ldisc)(struct tty_struct *tty);
385 void (*wait_until_sent)(struct tty_struct *tty, int timeout);
386 void (*send_xchar)(struct tty_struct *tty, char ch);
387 int (*tiocmget)(struct tty_struct *tty);
388 int (*tiocmset)(struct tty_struct *tty,
389 unsigned int set, unsigned int clear);
390 int (*resize)(struct tty_struct *tty, struct winsize *ws);
391 int (*get_icount)(struct tty_struct *tty,
392 struct serial_icounter_struct *icount);
393 int (*get_serial)(struct tty_struct *tty, struct serial_struct *p);
394 int (*set_serial)(struct tty_struct *tty, struct serial_struct *p);
395 void (*show_fdinfo)(struct tty_struct *tty, struct seq_file *m);
396 #ifdef CONFIG_CONSOLE_POLL
397 int (*poll_init)(struct tty_driver *driver, int line, char *options);
398 int (*poll_get_char)(struct tty_driver *driver, int line);
399 void (*poll_put_char)(struct tty_driver *driver, int line, char ch);
400 #endif
401 int (*proc_show)(struct seq_file *m, void *driver);
402 } __randomize_layout;
403
404 /**
405 * struct tty_driver -- driver for TTY devices
406 *
407 * @kref: reference counting. Reaching zero frees all the internals and the
408 * driver.
409 * @cdevs: allocated/registered character /dev devices
410 * @owner: modules owning this driver. Used drivers cannot be rmmod'ed.
411 * Automatically set by tty_alloc_driver().
412 * @driver_name: name of the driver used in /proc/tty
413 * @name: used for constructing /dev node name
414 * @name_base: used as a number base for constructing /dev node name
415 * @major: major /dev device number (zero for autoassignment)
416 * @minor_start: the first minor /dev device number
417 * @num: number of devices allocated
418 * @type: type of tty driver (%TTY_DRIVER_TYPE_)
419 * @subtype: subtype of tty driver (%SYSTEM_TYPE_, %PTY_TYPE_, %SERIAL_TYPE_)
420 * @init_termios: termios to set to each tty initially (e.g. %tty_std_termios)
421 * @flags: tty driver flags (%TTY_DRIVER_)
422 * @proc_entry: proc fs entry, used internally
423 * @other: driver of the linked tty; only used for the PTY driver
424 * @ttys: array of active &struct tty_struct, set by tty_standard_install()
425 * @ports: array of &struct tty_port; can be set during initialization by
426 * tty_port_link_device() and similar
427 * @termios: storage for termios at each TTY close for the next open
428 * @driver_state: pointer to driver's arbitrary data
429 * @ops: driver hooks for TTYs. Set them using tty_set_operations(). Use &struct
430 * tty_port helpers in them as much as possible.
431 * @tty_drivers: used internally to link tty_drivers together
432 *
433 * The usual handling of &struct tty_driver is to allocate it by
434 * tty_alloc_driver(), set up all the necessary members, and register it by
435 * tty_register_driver(). At last, the driver is torn down by calling
436 * tty_unregister_driver() followed by tty_driver_kref_put().
437 *
438 * The fields required to be set before calling tty_register_driver() include
439 * @driver_name, @name, @type, @subtype, @init_termios, and @ops.
440 */
441 struct tty_driver {
442 struct kref kref;
443 struct cdev **cdevs;
444 struct module *owner;
445 const char *driver_name;
446 const char *name;
447 int name_base;
448 int major;
449 int minor_start;
450 unsigned int num;
451 short type;
452 short subtype;
453 struct ktermios init_termios;
454 unsigned long flags;
455 struct proc_dir_entry *proc_entry;
456 struct tty_driver *other;
457
458 /*
459 * Pointer to the tty data structures
460 */
461 struct tty_struct **ttys;
462 struct tty_port **ports;
463 struct ktermios **termios;
464 void *driver_state;
465
466 /*
467 * Driver methods
468 */
469
470 const struct tty_operations *ops;
471 struct list_head tty_drivers;
472 } __randomize_layout;
473
474 extern struct list_head tty_drivers;
475
476 struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner,
477 unsigned long flags);
478 struct tty_driver *tty_find_polling_driver(char *name, int *line);
479
480 void tty_driver_kref_put(struct tty_driver *driver);
481
482 /* Use TTY_DRIVER_* flags below */
483 #define tty_alloc_driver(lines, flags) \
484 __tty_alloc_driver(lines, THIS_MODULE, flags)
485
tty_driver_kref_get(struct tty_driver * d)486 static inline struct tty_driver *tty_driver_kref_get(struct tty_driver *d)
487 {
488 kref_get(&d->kref);
489 return d;
490 }
491
tty_set_operations(struct tty_driver * driver,const struct tty_operations * op)492 static inline void tty_set_operations(struct tty_driver *driver,
493 const struct tty_operations *op)
494 {
495 driver->ops = op;
496 }
497
498 /**
499 * DOC: TTY Driver Flags
500 *
501 * TTY_DRIVER_RESET_TERMIOS
502 * Requests the tty layer to reset the termios setting when the last
503 * process has closed the device. Used for PTYs, in particular.
504 *
505 * TTY_DRIVER_REAL_RAW
506 * Indicates that the driver will guarantee not to set any special
507 * character handling flags if this is set for the tty:
508 *
509 * ``(IGNBRK || (!BRKINT && !PARMRK)) && (IGNPAR || !INPCK)``
510 *
511 * That is, if there is no reason for the driver to
512 * send notifications of parity and break characters up to the line
513 * driver, it won't do so. This allows the line driver to optimize for
514 * this case if this flag is set. (Note that there is also a promise, if
515 * the above case is true, not to signal overruns, either.)
516 *
517 * TTY_DRIVER_DYNAMIC_DEV
518 * The individual tty devices need to be registered with a call to
519 * tty_register_device() when the device is found in the system and
520 * unregistered with a call to tty_unregister_device() so the devices will
521 * be show up properly in sysfs. If not set, all &tty_driver.num entries
522 * will be created by the tty core in sysfs when tty_register_driver() is
523 * called. This is to be used by drivers that have tty devices that can
524 * appear and disappear while the main tty driver is registered with the
525 * tty core.
526 *
527 * TTY_DRIVER_DEVPTS_MEM
528 * Don't use the standard arrays (&tty_driver.ttys and
529 * &tty_driver.termios), instead use dynamic memory keyed through the
530 * devpts filesystem. This is only applicable to the PTY driver.
531 *
532 * TTY_DRIVER_HARDWARE_BREAK
533 * Hardware handles break signals. Pass the requested timeout to the
534 * &tty_operations.break_ctl instead of using a simple on/off interface.
535 *
536 * TTY_DRIVER_DYNAMIC_ALLOC
537 * Do not allocate structures which are needed per line for this driver
538 * (&tty_driver.ports) as it would waste memory. The driver will take
539 * care. This is only applicable to the PTY driver.
540 *
541 * TTY_DRIVER_UNNUMBERED_NODE
542 * Do not create numbered ``/dev`` nodes. For example, create
543 * ``/dev/ttyprintk`` and not ``/dev/ttyprintk0``. Applicable only when a
544 * driver for a single tty device is being allocated.
545 */
546 #define TTY_DRIVER_INSTALLED 0x0001
547 #define TTY_DRIVER_RESET_TERMIOS 0x0002
548 #define TTY_DRIVER_REAL_RAW 0x0004
549 #define TTY_DRIVER_DYNAMIC_DEV 0x0008
550 #define TTY_DRIVER_DEVPTS_MEM 0x0010
551 #define TTY_DRIVER_HARDWARE_BREAK 0x0020
552 #define TTY_DRIVER_DYNAMIC_ALLOC 0x0040
553 #define TTY_DRIVER_UNNUMBERED_NODE 0x0080
554
555 /* tty driver types */
556 #define TTY_DRIVER_TYPE_SYSTEM 0x0001
557 #define TTY_DRIVER_TYPE_CONSOLE 0x0002
558 #define TTY_DRIVER_TYPE_SERIAL 0x0003
559 #define TTY_DRIVER_TYPE_PTY 0x0004
560 #define TTY_DRIVER_TYPE_SCC 0x0005 /* scc driver */
561 #define TTY_DRIVER_TYPE_SYSCONS 0x0006
562
563 /* system subtypes (magic, used by tty_io.c) */
564 #define SYSTEM_TYPE_TTY 0x0001
565 #define SYSTEM_TYPE_CONSOLE 0x0002
566 #define SYSTEM_TYPE_SYSCONS 0x0003
567 #define SYSTEM_TYPE_SYSPTMX 0x0004
568
569 /* pty subtypes (magic, used by tty_io.c) */
570 #define PTY_TYPE_MASTER 0x0001
571 #define PTY_TYPE_SLAVE 0x0002
572
573 /* serial subtype definitions */
574 #define SERIAL_TYPE_NORMAL 1
575
576 int tty_register_driver(struct tty_driver *driver);
577 void tty_unregister_driver(struct tty_driver *driver);
578 struct device *tty_register_device(struct tty_driver *driver, unsigned index,
579 struct device *dev);
580 struct device *tty_register_device_attr(struct tty_driver *driver,
581 unsigned index, struct device *device, void *drvdata,
582 const struct attribute_group **attr_grp);
583 void tty_unregister_device(struct tty_driver *driver, unsigned index);
584
585 #ifdef CONFIG_PROC_FS
586 void proc_tty_register_driver(struct tty_driver *);
587 void proc_tty_unregister_driver(struct tty_driver *);
588 #else
proc_tty_register_driver(struct tty_driver * d)589 static inline void proc_tty_register_driver(struct tty_driver *d) {}
proc_tty_unregister_driver(struct tty_driver * d)590 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
591 #endif
592
593 #endif /* #ifdef _LINUX_TTY_DRIVER_H */
594